Wetting on sawtooth surface

As for the ideal smooth surface (Section 1.2.3 and Appendix B), the free energy change AF can be calculated as a function of 0M, when a liquid surface initially in a horizontal position (z = 0, 0M = 90°) rises to form a meniscus of height z and a contact angle 0M- The interfacial (AFs l and AFs 2) and potential (AFb) energy contributions need to be modified to take into account the particular geometry of 

For any cavity with a / value higher than / , d((5Fs) / d( 51) will be positive whatever the value of 1, so the cavity will not be infiltrated by the liquid. Equation (1.39) shows that composite interfaces can be produced only for non-wetting liquids and very rough surfaces. 

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